File: clean.sh
   1 #!/bin/sh
   2 
   3 # The MIT License (MIT)
   4 #
   5 # Copyright (c) 2026 pacman64
   6 #
   7 # Permission is hereby granted, free of charge, to any person obtaining a copy
   8 # of this software and associated documentation files (the "Software"), to deal
   9 # in the Software without restriction, including without limitation the rights
  10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11 # copies of the Software, and to permit persons to whom the Software is
  12 # furnished to do so, subject to the following conditions:
  13 #
  14 # The above copyright notice and this permission notice shall be included in
  15 # all copies or substantial portions of the Software.
  16 #
  17 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23 # SOFTWARE.
  24 
  25 
  26 # clean [options...] [command] [args...]
  27 #
  28 #
  29 # CLEAN the screen, after running the command given. When its standard output
  30 # is piped, no cleaning happens, and this script becomes a passthru.
  31 #
  32 # This tool doesn't clear the screen, but rather uses the alternative screen
  33 # buffer, so the original content of the terminal is restored when done.
  34 #
  35 # The options are, available both in single and double-dash versions
  36 #
  37 #   -h, -help       show this help message
  38 #   -v, -verbose    show error code if command given fails
  39 
  40 
  41 verbose=0
  42 
  43 case "$1" in
  44     -h|--h|-help|--help)
  45         awk '/^# +clean /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  46         exit 0
  47     ;;
  48 
  49     -v|--v|-verbose|--verbose) verbose=1; shift ;;
  50 
  51     --) shift ;;
  52 
  53     -*)
  54         printf "unsupported option '%s'\n" "$1" >&2
  55         exit 1
  56     ;;
  57 esac
  58 
  59 if [ $# -eq 0 ]; then
  60     awk '/^# +clean /, /^$/ { gsub(/^# ?/, ""); print }' "$0" >&2
  61     exit 1
  62 fi
  63 
  64 [ -p /dev/stdout ] && exec "$@"
  65 
  66 # restore previous screen contents when sent a SIGINT signal, which usually
  67 # happens by pressing Ctrl+C
  68 trap '
  69     tput -T xterm rmcup 2> /dev/null || printf "\033[?1049l\033[23;0;0t"
  70     exit 130
  71 ' INT
  72 
  73 tput -T xterm smcup 2> /dev/null || printf "\033[?1049h\033[22;0;0t"
  74 "$@"
  75 res=$?
  76 tput -T xterm rmcup 2> /dev/null || printf "\033[?1049l\033[23;0;0t"
  77 
  78 if [ "${verbose}" -eq 1 ] && [ "${res}" -ne 0 ]; then
  79     printf "command \"%s\" failed with error code %d\n" "$*" "${res}" >&2
  80 fi
  81 
  82 exit "${res}"